People are generally aware of the most common causes of hallucinations, like schizophrenia and a really high fever. But lesser known are the more rare causes; here are six you probably haven't heard about.

Narcissism And Lack Of Empathy Unlikely To Get You Friends But May Help You Snag That Promotion

A little bit of narcissism may go a very long way, especially in the workplace. A study from last year found that those who can effortlessly climb the corporate ladder usually have two personality traits in common: a general lack of empathy and a whole lot of self-adoration.

The Dark Triad

Unfortunately, getting promoted in your position may not have as much to do with your work ethic and ability to deliver as it does with your ability to manipulate others and catch the attention of your superiors, The Wall Street Journal reported. According to a study published in the Journal of Organizational Behavior, your personality may determine your likeliness to succeed.

What psychologists refer to as the "dark triad" is a combination of personality traits that are found in many successful individuals. Those who possess the dark triad traits are often manipulative, have a tendency to influence others for self-gain, have narcissism, anti-social personalities, and a general lack of concern for others. Although it may go without saying that, overall, these traits are less than desirable, in small doses they may help you to get that promotion you’ve been wanting.

Nice Guys Finish Last

It’s not that bosses tend to favor the rude brute of the office, but they are likely to notice them and this makes all the difference. By making an effort to always be at the center of attention, you're more likely to leave an impression on your supervisor or potential clients. Due to the fact that narcissists generally like to be seen at their best, they also tend to excel in training programs. Those with dark triad traits are viewed as more charming, assertive, and appear to possess adequate leadership qualities. “One of the reasons these people climb so high in the company is that they're very forceful," James D. Ratley, president of the Association of Certified Fraud Examiners, explained to The Wall Street Journal.

It’s Not A Dark Side, It’s A Skill

Simply possessing these personality traits aren’t always enough. You need to be able to develop them into a skill. "One of the reasons these people climb so high in the company is that they're very forceful," Ratley explained. Karma does tend to catch up on these individuals if they don’t play their cards right.

The beginning of the end often occurs when these traits become too expressive in one’s personality. “They think the rules don’t apply to them,” Ratley said. An example of this would be former HealthSouth Corp. CEO Richard Scrushy, who may have been an excellent boss, but eventually saw his position revoked after being caught in the midst of a $2.7 billion accounting fraud. Despite losing his position and serving a brief jail sentence, Scrushy insists that psychologists have his personality all wrong. “I don't think it's a 'dark side.' It's a skill, to be able to build a business from scratch," Scrushy said.

Silver Lining

Having dark triad aspects to your personality is not always a bad thing. Manipulative individuals tend to be skilled negotiators and make great commanders due to their love of combat and ease at forming alliances. Although impulsive and thrill-seeking, individuals with this personality trait tend to be more creative and are more likely to “think outside the box.” Of course, being at the center of attention is likely to annoy others in the board room, but at least you’ll be bound to make a good first impression and are likely to pitch ideas with genuine enthusiasm rather than hesitation.